Radiotelegraphy.



L. M. COCKADAY.

RADIOTELEGRAPHY,

APPLICATION FILED OCT. 2L ISH]4 15,299,823. l Patented Apr. 8,19l9. a sHEEIs-sHEr 5 uvam/(oz L. M. COCKADAY.

HADIUTELEGRAPHY.

APPLICATION FILED OCT. 27. Wi?

lzltcutvd Apr. S, W19.

3 SHEES SHEET 2.

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fjfg- 5 57 @uvam/haz L. M. COCKADAY.

RADIOTELEGRAPHY.

APPLICAHGN man ocr. 21. mu.

l 9299,823 Patented Aw. 8,1919.

3 SHEETS-SHEET 3.

LAURENCE M. COCKADAY, 0F NEW YORKLN. Y.

RADIOTELEGRAPHY.

Specification of Letters Patent.

Patenten apr. el. aora.

Application led October 27, 1917. Serial No. 199,305.

To all whom t may concern.'

Be it known that I, LAUREN/Cn M. COCHA- DAY, a citizen of the United States, and a resident of the borough of Manhattan, in the city of New York, county and State of New York. have invented certain new and high potential electrical oscillations from a direct. current or other supply.

According to my invention there are three circuits employed: the, power circuit, the closed circuit and the aeral circuit. The current source of energy (preferably direct current) is made and broken by an interrupter hereinafter described which controls the frequency of the applied current in, the power circuit, thereby inducing in the Iclosed circuit a series of high potential impacts which are uniformly spaced and separately stored up until discharged through a timing spark-gap 'device which controls the time of discharge of said impacts and as a result of these discharges energizing by induction the aerial circuit with a series of groups of high potential high frequency oscillations of dccaying amplitude and causing wave trains to be emitted from the aerial in the form of Hertzian waves.

The construction just referred to employs a step-up transformer referred to as an initial step-up transformer and also a second transformer transformer. The primary coil of the initial stepup transformer is in the power circuit;

the secondary coil ot the initial step-up' transformer and the primary coily of the spark-gap device are m the closed clrcuit; and the secondary coil of the oscillation transformer as well as the aerial are in theV aerial circlut.

As herein illustrated and described the invention, in lts preferred fornuis dlrected to a construction m which the sparking is established and interrupted at a time when referred to as the oscillation no current is being supplied to the primary 'coil of the initial transformer. nthis form of apparatus' a condenser is an lmportant element and is-connected in the closed circuit and serves to store the energy until discharged by the sparkine'. The invention, however, is not limited to a construction in which the sparking takes place at such a. time for it eomprehends or includes a construction in which the sparking may take place at a time when the current is being supplied to the primary coil of the initial stepmp transformer-in other words, at a time when the condenser and the secondary coil to which the condenser is connected has an induced electrical current passingto or through it. Such Va construction 1s also illustrated. l

In the latter construction it might be possible to eliminate the condenser or make it small, but the resulting Itierzian waves would' not be so powerful as in the preferred form of apparatus.

in the construction of an apparatus for performing the invention it is desirable that the. impulses finally received by the primary of the oscillation transformer be in the form ot' damped sets of high potentail oscillations of high frequency and also that the inten rupter employed 1n the power circult should operate without areing on breaking the current, and according to my invention there is provided a means for accomplishing these ends.

In the preferred form of apparatus the interruptor and the timing spark-gap device are so constructed that when the interrupter is completing the power circuit the timing spark-gap device is out of sparking' position, no discharge taking-plaee in the spark-gap until the interrupter has broken the power circuit. During the time when the power circuit is broken the timing spark-gap device moves into sparking position and out of said position, and the same cycle of operations is successively repeated. From thisit will be seen' that the condenser which is ineluded in the closed circuit is charged and discharged alternately, the function of charge being governed by the interrupt-er in the power circuit and the function of discharge being governed by the timing sparkaov gap device in the closed circuit, the operation of charging the condenser by the power circuit current and the discharging of the condenser occurring in different periods of time.

The invention relates to the features above referred to as well as to others which will appear in the course of the following description and in the accompanying claims.

As illustrating certain specific embodiments of the invention reference is made to the drawings forminga part of this specification, in which drawings,

-Figure l is a diagrammatic view illustrating the essential elements of a radiotelegraph apparatus constructed for performing the invention. In this figure a preferred form of apparatus is illustrated.

Fig. is a side elevational view of a combined switch and spark-gap device; viz., of a combined interrupter and timing sparkgap device.

Fig. 3 is a vertical sectional view of the combined interrupter and timing spark-gap device shown in Fig. 2.

Fig. 4 is a vertical sectional view of the spark-gap portion of said device and 1s a' view taken as on the line' 4 4 of Fig. 3, looking in the direction of the arrows.-

Fig. 5 is a view taken as on the plane indicated by the line of Fig. 2 looking in the direction of the arrows. In this ligure there is shown a portion of the switch mechanism of the combined switcli and sparkgap device.

Fig. (l is a view taken as on .the plane indicated by the line 6 6 of Fig. 5, looking in the direction of the arrows.

Fig. 7 is a diagrammatic view of radiotelegraph apparatus which is comprehended or included within my invention. In this form of apparatus the sparking through the timing spark-gap device may take place when current is being supplied from the power circuit due to the switch ofsaid circuit being closed.

A source of current supply, preferably a direct current of constant potential, is designated by E and this is included in a powery circuit PG which comprises line i., primary coil '3 of an initial step-up transformer IT, lines4, 5, (i and 7, stationary contact c1, movable contact c", stationary contact c3 of a switch C, lines 8, 9, 10 and 11, key K, line l2 and hand switch H.

Inv the construction shown the. contact c2 is any one of a number of such contacts that are uniformly spaced and insulated from each other and that are carried on a rotary disk D that preferably provides the insulating material for separating the contacts c2' The switch "C whic-h :includes the '18 of the oscillation transformer OT, lines 19, 20, 21 and 22, stationary terminal member g1, rotary bridge member g2, stationary terminal g3. lines 23, 2J: and 25.

The terminal member g1, rotary bridge (/2 and terminal member g3 may be considered to constitute the essential members of the rotary spark-gap device SG. This rotary spark-gap device constitutes the timing spark-gap that waspreviously referred to and which is hereinafter described more in detail. The secondary coil of the oscillation transformer OT is designated by the reference character 26 and is included in an open or aerial circuit. One terminall of this secondary coil 26 is shown as beingconnected by lines 27 and 28 to an aerial A. The function of an aerial is well known in the art and may be described as an aerial member, or members, for receiving or transmitting electrical energy and particularly in wireless y telegraphy work.

as being connected through the line 20, am-

meter M and line 30 to switch s so that said secondary coil '26 can be connected to not in use. The key K indicated in said circuit can be utilized to transmit messages by means of a telegraphic code. A' condenser X connected by lines 81 and 32 is shunted across the terminals of the switch (l. A condenser'Y is shunted across the terminals of the secondary coil of `the initial transformer by means of lines and 34'.

In the diagrammatic viewshown in'Fig. 1 it will 'be observed that there are a number of equally spaced vmovable contact members 02 which are secured to the face of the Wheel or disk D! This wheel or disk D may be referred to as a rotary contact carrying member since it is mounted upon and secured to the rotating shaft 'S and carries the spaced contacts c2 just referred to. Therc'is also mounted upon this shaft S and secured thereto the rotary bridge member z/2 of the spark-gap device SG and this bridge member g2 has a number of equally spaced terminal members grt arranged in pairs so that when any one of the spaced terminal members gt is opposite the stationary terminal g another of the spaced terminal members g* will be oppoiste the other stationary terminal member g3. V

ln the construction shown with the rotary bridgemember directly connected to the wheel or disk-D, whereby both of said members make the same revolutions per minute, then in that case there is exactly the same number of teeth or terminals gt upon the rotary bridge member g2 as there are contacts c2 upon the wheel or disk D. tThe arrangement is also such that each time a contact c2 completes the closing of the switch C then the terminals gt are in such position relative to the stationary 'terminalsgl and g3 that no sparking can take place; or, in other words, each time the power circuit PC is closed by the switch C the members of the spark-gap device SG are in such a position that no sparking can take -place in the closed circuit OC, the condenser Y receiving the charge and holding it until the power circuit is broken on account of rotationof members being mounted on. shaft,

which same rotation "will afterward bring Y the spark-gap into a position -whereby the condenser can discharge its energy across the gap'. The device which comprises the shaft S, the members of. the spark-gap de-` vice SG and the members of the switch C may be considered as a combined switchi and spark-gap device,and this is properly referred to as a device comprising a combined interrupter Aand timing spark-gap since the switch serves as an interrupter and the rotary bridge Vmember,'which is connected to the switch, serves to time the sparking that takes place in the spark-gap device.

One form of such device is shown in Figs. Q'to 6. In said figures the casing of the device is designated by B and it comprises the upper and lower halves b and b1 which are held in assembled position in any suitable manner as by means of bolts 35.l The shaft shown in these tigures'is designated by S and corresponds in its function to the shaft S shown in Fig. 1. Thisshaft may be driven as by a motor indicated diagrammatically at P. Tt-will be observedthat the casin isdivided into two compartments, 36- and 3 by the partition 38. Upon the shaft S the disk D heretofore referred to is mounted and secured in place by means of a screw 39, as shown in Fig. 3. The electrical bridging element of the rotar bridge member g2. is 1n the form of a meta ring 40 having the equally spaced terminals gt thereupon and this ring 40 is held in 'place by means of screws '.41 on a bodv of insulating material 42. .This body ot insulating material 42 is lin thehtorm 'of a rotary carrier A which is held in place on the shaft S byt means of a screw 43. The stationary terminals g1 and g3 are held in place in the casing B by means of'holders 44 and screws 45. The holders 44 are of insulating material whereby the terminals g1 and g3 are each insulated from the casing. From what has been stated in previous portions of this specification it will be clear that the switch C is closed each time amovable contact c2 engages the stationary contacts c1 and c3,

said'ccntacts c1 and c3 being clearly shown in Figs. A5 and 6. Each of the movable contacts c2 is secured in place on the wheel or disk by means of a screw 46. The wheel or disk D is of course made of insulating material. The stationary contacts c1 and care preferably forced continuously againstfthe contact carrying member or wheel D by means of springs a7 and 48 which are respectively in the sockets 4:9 and 50. These sockets are` insulated from the casing in which they are located in any suitable manner, as by meansof insulating material at 51 and 52 respectively.

It will be observed that the width or peripheral dimension :c of the contacts c2 is less than the peripheral distance y betweenv such a manner that the several contacts c2 are insulated from each' other. As the motor P rotatesfthe wheel the circuit is successively closed and opened at the switch C by the contacts c2 each successively moving into and out of engagementv with the stationary contacts c1 and c3. The motor P rotates so that the switch C is broken, for example,

500 times per second and this results in 500 cycles per second in the system. This number of cycles is of high frequency and any device which has. 400 cycles per second or moreV comes within the'r term high frequency as employed in this specification.

The spark frequency which is a function of the number of discharges bridging the gap per second canbe readily changed in the system herein shown anddescribed by changing the vspeed of the motor which operates the shaft S and consequently any desired frequency can be vobtained by a proper regulation 'of the speed of rotation of this shaft. Therefore, according to the system herein described an electric current can be converted into a series of impacts or pulsations which indpce' a Series of oscillations in a closed or oscillating circuit and which, on being discharged through the rotary spark-gap in turn induce a wave train Vin an open circuit in which there is included,

an aerial. This wave train has a low decrement or 1s a ure weve and thereis no reaction from t e open circuit back upon'saxd' closed or oscillating circuithand this applies iso no mattei' what is the wave length that is employed 1n said open circuit.

In the apparatus which I have constructed A A short group of oscillations each time discharge occurs in a closed circuit andfthese groups are damped out before reaction from the secondary coil of the oscillation transformer can take place, thus resulting in a wave train ot'- exceedingly low decrement in the open or antenna circuit regardless of the wave length ot' said circuit. I

vAnother advantage of thisl system is that the condenser Y-the high potential condenser that is shunted across the lines of the secondary coil of the step-up initial transformer I'l`--can be made of very small# -apacity on account ot' the instantaneous high poten-tial currentinduced in said secondary coil. Due to the fact that the power Circuit closed only for a short time it is necessary to use at the, mostonly af small condenser to shunt the contacts of the switch C.4 It will therefore be seen that according to my System there is an advantage in overcoming the necessity of using large, condensers in the power circuit. The employment of a small condenser, however, in the closed circuit makes it possible. to work the system on very short -wa ve lengths.

The electrical energy employed in the apparatus and which is supplied to the power circuit is preferably that received from a direct current generator, but it might be derived from a storage battery, or possibly even from an alternating current generator, but the results fromy the latter` would notl be as satisfactory as with the, direct current generator or battery.

The detailed description previously given particulally applies to the construction illustrated in Fig. 1. According to the construction of said figure the sparking through the timing spark-gap device takes place only when the current in the power circuit is interruptedl In. Fig. 47 it will be observed that the timing .spark-gap is arranged so that sparking takes place when the current is being supplied through the power circuit) -this because the terminals L of the rotar spark-gap membe are adjacent to the stationarytern1nu\lsg,f/" when a. movable conv tact c2 engages the stationary contacts 01, c3.

ASuch a condition can be readily obtained by 'modifications ywithout departing from the spirit and scope of the invention.

What I claim is: i

l. In high frequency apparatus having a main supply circuit, 'the combination of4 a rotary make and break .device controlling said circuit and a rotary spark gap coperat-ing with saidy make' and break device and rotating in synchronis'm therewith, said make and break device and spark gap being adjustableA relatively to' each. other to vary the functioning of the spark gap relatively to the make and break device as may be de' sired. v i

A 2. In an apparatus' for producing high frequency electrical impulses, the combination of a primarv and Secondary circuit, an interrupter in the primary circuit, and a spark gap in the secondary circuit synchronously and adjnstably coperating therewith. l

3L The method of producing high 'frequency eleetri al impulses, comprising positively interrupting ar primary supply of energy, and synchronously and selectively discharging an induced secondaryhigh quency oscillation.

l. The method of producing high frequency electrical impulses. comprising positively interrupting a primary supply of energy and selectively vdischarging an induced secondary high frequency oscillation.

5. In radiotelegraphy, an apparatus coinprising in combination a power circuit having therein the primary' coil of an initial step-up transformer, an oscillating circuit having therein the secondary coil of said initial transformer, a condenser and the primary coil ofan oscillation transformer, said apparatus comprising` a rotarY make and break device for successively making and breaking the power circuit, and a rotary spark gap device in the oscillating circuit rotating in s vlu-hronism with said make and break device.

(l. In radiotelegraphy. an apparatus com-V freing and breaking .,the power circuit, and a rotary spark gap device coperatin'gn with said make and break device and rotating in stif'nchronism therewith.

7. In an apparatus for producing high frequency eiectri -al impulses, the combination of a primary and a secondary circuii, an intcrrupter in the primary circuit. and

a synchronously oporatmi Spark gap in the svunndalw 'ilcuit.

ThiaA spvcification signod and witnessed this 26th day of Ocioiwi', A. D. 1917.

LAI'HECE M. FOUKDY. Signwi in the presence of- MCGHANN, M. F. Km'rixc. 

